This CO2-sucking rock takes eons to form naturally. Now we can grow it in weeks

Could lab-grown magnesite help fight back against climate change? That’s what a new research project carried out by investigators from Trent University, in Ontario, Canada and The University of British Columbia suggests. Magnesite, a.k.a. magnesium carbonate, is capable of sucking up carbon dioxide (CO2) at an impressive rate, with one metric ton of magnesite capturing half as much CO2. Unfortunately, it can take thousands of years to grow — reduced to just 72 days using the new process.

“Although many technologies for sequestering CO2 have been shown to work, the challenge is finding ways to do this economically and at a large scale,” Ian Power, an environmental geoscientist at Trent University, told Digital Trends. “Magnesite can form at high temperatures — say, in industrial reactors — but high temperatures means greater energy input, and that would likely mean higher cost. We demonstrated that it is possible to accelerate the formation of magnesite, at room temperature, from hundreds to thousands of years [down to just] tens of days.”

The reason it is so important to sequester CO2 is because, even with the amount of greenhouse gases which have been pumped into the environment, the climate will continue to get warmer — even if we were to stop all emissions immediately. As a result, what is needed is a way to get back some of the greenhouse gases already in the atmosphere.

The room temperature process pioneered by the researchers used microspheres made of polystyrene as a catalyst to trigger the reaction process, helping the magnesite to form. These microspheres weren’t changed by the production of magnesite, meaning that they could be reused.

Given that the world currently emits around 40 billion tonnes of CO2 per year, a whole lot of this material would be needed for this to have a noticeable impact — but being able to produce it more rapidly is definitely a good start. Next, the researchers want to work on ways to scale up the process.

“Our study was at the laboratory scale,” Power continued. “We demonstrated a very novel approach to forming magnesite. We [now] want to better understand the fundamental science even better, and possibly [also] explore how bacteria could be used to form magnesite. Bacteria can have similar cell walls as the polystyrene microspheres we used in our experiments, and have been shown to mediate carbonate formation.”

A paper describing the work was recently published in the journal Crystal Growth & Design. Powers’ co-authors on the project included Paul Kenward, Gregory Dipple, and Mati Raudsepp from the University of British Columbia.